1. Field of the Invention
The present invention relates to a method and system for selecting a broadcast voice channel from a plurality of broadcast voice channels provided in a telephone network as a telephone service.
2. Description of the Related Art
A broadcast voice service is provided in a telephone network for making subscribers listen to broadcast voices sent from a plurality of broadcast stations.
FIG. 1 is an example illustrating a selecting system of the related art in a telephone network 5. In FIG. 1, a plurality of radio broadcast receivers (RADIO Rx) 3.sub.1 to 3.sub.n located at a station of a toll switch (TS) 51 receive a plurality of radio signals 2.sub.1 to 2.sub.n transmitted from a plurality of radio broadcast stations (RADIO STN) 1.sub.1 to 1.sub.n respectively and convert the radio signals 2.sub.1 to 2.sub.n into a plurality of voice signals 7.sub.1 to 7.sub.n each having a voice bandwidth matched to a specific character of lines in telephone network 5. The voice signals 7.sub.1 to 7.sub.n are sent to trunks (TRKs) (511.sub.1 to 511.sub.n) in TS 51 through a plurality of line controllers (LINE CONT) 4.sub.1 to 4.sub.n respectively, located between RADIO Rxes 3.sub.1 to 3.sub.n and TRKs 511.sub.1 to 511.sub.n respectively.
In telephone network 5, there are plurality of TSes 51, local switches (LSes) 52 connected to TS 51 and subscribers (SUBs) 6 connected to LS 52. One SUB 6, TS 51 and LS 52 are representatively depicted in FIG. 1. The telephone network 5 provides special dialing numbers (DN.sub.1 to DN.sub.n) for servicing the broadcast voices from RADIO STNs 1.sub.1 to 1.sub.n to SUB 6. When, SUB 6 dials DN.sub.1 comprised of, for example, a toll number of TS 51 and a special number 1XX1, a speech path network 512 in telephone network 5 connects SUB 6 with TRK 511.sub.1 correspondent to RADIO STN 1.sub.1. Then, TRK 511.sub.1 sends a triggering signal to LINE CONT 4.sub.1 so that LINE CONT 4.sub.1 sends a voice signal output from RADIO Rx 3.sub.1, back to SUB 6 through speech path network 512 and LS 52. Thus, SUB 6 can select the broadcast voice from RADIO STN 1.sub.1 by dialing.
Listening to a broadcast voice from RADIO STN .sub.1 1, if SUB 6 wants to listen to another broadcast voice from, for example, RADIO STN 1.sub.n, SUB 6 releases the connection with TRK 511.sub.1 once and makes another call by dialing DN.sub.n comprised of the toll number of TS 51 and another special number 1XXn, so as to connect to TRK 511.sub.n. When TRK 511.sub.n is connected with SIB 6, TRK 511.sub.n produces a triggering signal and sends it to LINE CONT 4.sub.n so that LINE CONT 4.sub.n sends the broadcast voice correspondent to RADIO STN 1.sub.n, back to SUB 6 through TRK.sub.n, speech path network 512 and LS 52.